Classification and Management of Wetlands in the Western Kentucky Coal Field

This is the first research report of a three-year project on wetland identification and management criteria in the western Kentucky coal field. The region is approximately 12,000 square kilometers and, due to its slight relief, contains many wetlands, some contiguous with surface coal mining operations. The overall objectives of the research project are 1) to identify, classify, and map wetlands in the western Kentucky coal field; 2) to evaluate the major biotic and abiotic factors that affect those wetlands; and 3) to develop strategies for the proper management of those wetlands. The first report of this three-year project has involved the following tasks related to wetlands in the coal fields of western Kentucky: establishment of three intensive study sites in major wetlands for identification and assessment of management impacts, sampling tripe in May, July, and September to the intensive study sites, to measure water quality and ecological structure, development of a classification specifically for wetlands in western Kentucky and an application of the classification to the three intensive study sites, and development of conceptual models of the region, watersheds, and specific ecosystems, and preliminary simulations of a wetland model. Our specific sites in western Kentucky are Cypress Creek Wetlands in Muhlenberg County, which are affected by mine drainage and channelization; Clear Creek Swamp in Hopkins County, which is affected by mine drainage and higher water levels; and Henderson Sloughs in Henderson County, which are affected by oil wells and clearing for agriculture. Preliminary analysis of field surveys demonstrates that several activities, particularly coal mining and oil \u27extraction, may affect the health of wetlands in western Kentucky. Drainage, logging, channelization, and impoundments have also caused significant alterations

Integrated Sr isotope variations and sea-level history of Middle to Upper Cambrian platform carbonates: Implications for the evolution of Cambrian seawater 87 Sr/ 86 Sr

ABSTRACT A high-resolution Sr isotope study of Middle to Upper Cambrian platform carbonates of the southern Great Basin significantly refines the structure of the existing seawater Sr isotope curve. Samples were selected using rigorous stratigraphic, petrographic, and geochemical criteria in order to minimize the effects of diagenetic alteration and contamination from noncarbonate components

Structural Basis for Functional Tetramerization of Lentiviral Integrase

Experimental evidence suggests that a tetramer of integrase (IN) is the protagonist of the concerted strand transfer reaction, whereby both ends of retroviral DNA are inserted into a host cell chromosome. Herein we present two crystal structures containing the N-terminal and the catalytic core domains of maedi-visna virus IN in complex with the IN binding domain of the common lentiviral integration co-factor LEDGF. The structures reveal that the dimer-of-dimers architecture of the IN tetramer is stabilized by swapping N-terminal domains between the inner pair of monomers poised to execute catalytic function. Comparison of four independent IN tetramers in our crystal structures elucidate the basis for the closure of the highly flexible dimer-dimer interface, allowing us to model how a pair of active sites become situated for concerted integration. Using a range of complementary approaches, we demonstrate that the dimer-dimer interface is essential for HIV-1 IN tetramerization, concerted integration in vitro, and virus infectivity. Our structures moreover highlight adaptable changes at the interfaces of individual IN dimers that allow divergent lentiviruses to utilize a highly-conserved, common integration co-factor

In Support of a Patient-Driven Initiative and Petition to Lower the High Price of Cancer Drugs

Comment in Lowering the High Cost of Cancer Drugs--III. [Mayo Clin Proc. 2016] Lowering the High Cost of Cancer Drugs--I. [Mayo Clin Proc. 2016] Lowering the High Cost of Cancer Drugs--IV. [Mayo Clin Proc. 2016] In Reply--Lowering the High Cost of Cancer Drugs. [Mayo Clin Proc. 2016] US oncologists call for government regulation to curb drug price rises. [BMJ. 2015